Integrated apparatus, exhaust gas post-processing system, and control method

ABSTRACT

An integrated apparatus of a pump and a nozzle, comprising a pump component and a nozzle component. The pump component comprises a motor housing assembly, a magnetic cover component and a pump housing assembly. The motor housing assembly comprises a magnetic screening cover and a motor coil. The motor housing assembly is fixed to the pump housing assembly by means of a method of rolling or welding. The pump housing assembly comprises an inlet pathway, which is in communication with a pump, and an outlet pathway, the outlet pathway being in communication with the nozzle component. The pump housing assembly also comprises a first gear assembly and a second gear assembly which are mutually engaged. The nozzle component comprises a nozzle assembly and a water cooling base, wherein the nozzle assembly comprises a nozzle coil for use in driving the nozzle. The integrated apparatus has a simple and compact structure, and high precision control. In addition, also provided is an exhaust gas post treatment system and a control method.

This application claims the priority of Chinese patent application no.201710042454.9 with invention title “Integrated apparatus, exhaust gaspost-processing system, and control method”, filed on Jan. 20, 2017, theentire content of which is incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to an integrated apparatus, an exhaust gaspost-processing system and a control method, in the technical field ofengine exhaust gas post-processing.

BACKGROUND ART

As emissions standards for internal combustion engine vehicles becomeever more stringent, selective catalytic reduction (SCR) is generallyused as a post-processing technology in the industry at present, withthe injection of a urea solution into exhaust gas being installedupstream of the SCR, in order to reduce the amount of harmful substancessuch as nitrogen oxides in exhaust gas. The urea solution undergoeshydrolysis and pyrolysis to generate ammonia, which undergoes a chemicalreaction with nitrogen oxides, etc., thereby reducing the concentrationof harmful substances.

At present, urea injection systems on the market generally comprise airassistance systems and non-air assistance systems. Of course, regardlessof the type of system, they all comprise a urea tank assembly, a pumpsupply unit connected to the urea tank assembly via a low-pressurepipeline, a nozzle module connected to the pump supply unit via ahigh-pressure pipeline, and a controller. The pump supply unit comprisesa urea pump and a pressure sensor, etc.; the nozzle module comprises aurea nozzle, etc. The urea pump and the urea nozzle are separated by alarge distance, and connected to each other via a urea pipe. Inaddition, existing urea injection systems contain a large number ofcomponents, are complex to install and have a high cost.

For these reasons, there is an urgent need to provide a novel technicalsolution.

CONTENT OF THE INVENTION

An object of the present invention is to provide an integrated apparatuswith relatively precise control, an exhaust gas post-processing systemand a control method.

To achieve the abovementioned object, the present invention employs thefollowing technical solution:

An integrated apparatus of a pump and a nozzle, wherein the pump is usedfor pumping a fluid medium toward the nozzle, and the nozzle is used forinjecting the fluid medium into intake gas or exhaust gas of an engine;the integrated apparatus comprises a pump component and a nozzlecomponent; the pump component comprises an electric machine casingassembly, a magnetic cover component at least partially located in theelectric machine casing assembly, and a pump housing assemblycooperating with the electric machine casing assembly; the electricmachine casing assembly comprises an electromagnetic shielding cover,and an electric machine coil at least partially located in theelectromagnetic shielding cover; the magnetic cover component comprisesa metal cover at least partially inserted into the electric machinecoil, and a rotor received in the metal cover; the electric machinecasing assembly and the pump housing assembly are fixed together by rollextrusion or welding; the pump housing assembly comprises an inletpassage located upstream of the pump and in communication with the pump,and an outlet passage located downstream of the pump and incommunication with the pump, wherein the outlet passage is incommunication with the nozzle component; the pump housing assemblyfurther comprises a first gear component and a second gear componentmeshed with each other, wherein the first gear component comprises afirst gear shaft and a first gear, the second gear component comprises asecond gear shaft and a second gear, the first gear and the second gearbeing meshed with each other, and the rotor being fixed to the firstgear shaft; the nozzle component comprises a nozzle assembly, and awater-cooled base connected in a surrounding manner at the outside ofthe nozzle assembly, wherein the nozzle assembly comprises a nozzle coilfor driving the nozzle.

In a further improved technical solution of the present invention, thepump is a urea pump, the nozzle is a urea nozzle, and the fluid mediumis a urea solution.

In a further improved technical solution of the present invention, thepump is a fuel pump, the nozzle is a fuel nozzle, and the fluid mediumis a fuel.

In a further improved technical solution of the present invention, thecontroller subjects the urea pump and the urea nozzle respectively toindependent control; the electric machine casing assembly comprises acontroller, the controller comprising a circuit board, with the electricmachine coil and the nozzle coil both being connected to the circuitboard.

In a further improved technical solution of the present invention, theintegrated apparatus comprises a sensor, in communication with theoutlet passage in order to detect temperature and pressure, and anoverflow element connected between the outlet passage and the inletpassage.

In a further improved technical solution of the present invention, thefirst gear shaft is a driving shaft, the second gear shaft is a drivenshaft, and the first gear shaft is higher than the second gear shaft.

In a further improved technical solution of the present invention, afreeze-resistant body located above the rotor is further provided in themetal cover, the freeze-resistant body being compressible in order toabsorb an expansion volume caused by the freezing of urea.

In a further improved technical solution of the present invention, thepump component further comprises an elastic body received in the metalcover and located below the rotor, the elastic body being compressiblein order to absorb an expansion volume caused by the freezing of urea.

In a further improved technical solution of the present invention, thepump housing assembly is provided with a gear slot receiving the firstgear and the second gear, the first gear and the second gear are meshedexternally, one side of the gear slot is provided with a liquid entrycavity in communication with the inlet passage, and another side of thegear slot is provided with a liquid exit cavity in communication withthe outlet passage.

In a further improved technical solution of the present invention, thepump housing assembly is further provided with a first freeze-resistantrod located in the liquid entry cavity and a second freeze-resistant rodlocated in the liquid exit cavity; the first freeze-resistant rod andthe second freeze-resistant rod are both compressible when urea freezes.

In a further improved technical solution of the present invention, thenozzle assembly comprises a magnetic part interacting with the nozzlecoil, a first sleeve at least partially receiving the magnetic part, avalve needle part located below the magnetic part, a second sleeve atleast partially receiving the valve needle part, a spring acting betweenthe magnetic part and the valve needle part, a valve seat cooperatingwith the valve needle part, and a rotational flow plate which ismanufactured separately from the valve seat and is in close abutmentwith the valve seat; the rotational flow plate is provided with a numberof rotational flow grooves.

In a further improved technical solution of the present invention, thenozzle coil is located at the periphery of the magnetic part, the valveneedle part is provided with a valve needle, the first sleeve and thesecond sleeve are fixed together to form a space around the periphery ofthe valve needle part, the valve needle is provided with a through-holein communication with the space, the second sleeve is provided with acommunication groove establishing communication between the space andthe rotational flow grooves, and the valve seat is provided with aninjection hole cooperating with the valve needle.

In a further improved technical solution of the present invention, theelectric machine casing assembly is provided with an injection-moldedconnection insertion member electrically connected to the circuit board,a number of electronic components are mounted on the circuit board, andthe electric machine casing assembly further comprises a heatdissipating pad covering a surface of the electronic components.

In a further improved technical solution of the present invention, themagnetic cover component comprises a sheet part located below the metalcover, the sheet part being fixed to the pump housing assembly by meansof a number of screws.

In a further improved technical solution of the present invention, thepump housing assembly comprises a first housing, the first housingcomprising a first upper surface, a first lower surface and a firstside, wherein the first upper surface is provided with a first annulargroove, a first island surrounded by the first annular groove, and afirst sealing ring received in the first annular groove, with the sheetpart pressing down on the first sealing ring; the first island isprovided with a first positioning hole running through the first lowersurface, and a second positioning hole running through the first lowersurface; the urea pump comprises a first shaft sleeve received in thefirst positioning hole, and a second shaft sleeve received in the secondpositioning hole, wherein the first gear shaft is inserted into thefirst shaft sleeve, and the second gear shaft is inserted into thesecond shaft sleeve.

In a further improved technical solution of the present invention, thefirst lower surface is provided with a first load release grooveestablishing communication between the first positioning hole and thesecond positioning hole.

In a further improved technical solution of the present invention, thefirst island further comprises a first flow-guiding groove runningthrough the first upper surface and in communication with the secondpositioning hole, and a first outlet hole running through the firstupper surface and in communication with the liquid exit cavity; thefirst upper surface is further provided with a sensor receiving hole,located at a side of the first island and used for receiving a sensor,and the integrated apparatus comprises the sensor for detectingtemperature and pressure; the first housing is further provided with asecond outlet hole in communication with the sensor receiving hole.

In a further improved technical solution of the present invention, thefirst housing is provided with an overflow element receiving slot, andthe integrated apparatus is provided with an overflow element mounted inthe overflow element receiving slot; when a pressure of the outletpassage is higher than a set value, the overflow element opens in orderto return a portion of the urea solution into the inlet passage.

In a further improved technical solution of the present invention, thepump housing assembly comprises a second housing, located below thefirst housing and connected to the first housing; the second housingcomprises a second upper surface and a second lower surface, with thegear slot running through the second upper surface and the second lowersurface.

In a further improved technical solution of the present invention, thepump housing assembly comprises a third housing, located below thesecond housing and connected to the second housing; the third housingcomprises a body part, and a protruding part extending downward from thebody part, wherein the body part is provided with a third upper surface,with the third upper surface being provided with a third annular grooveand a third island surrounded by the third annular groove; the thirdisland is provided with a third positioning hole and a fourthpositioning hole running through the third upper surface, the thirdpositioning hole and the fourth positioning hole extending into theprotruding part; the urea pump comprises a third shaft sleeve receivedin the third positioning hole, and a fourth shaft sleeve received in thefourth positioning hole, wherein the first gear shaft is inserted intothe third shaft sleeve, and the second gear shaft is inserted into thefourth shaft sleeve.

In a further improved technical solution of the present invention, thethird island is provided with a second flow-guiding groove and a thirdflow-guiding groove running through the third upper surface, wherein thesecond flow-guiding groove is in communication with the thirdpositioning hole, and the third flow-guiding groove is in communicationwith the fourth positioning hole.

In a further improved technical solution of the present invention, thenozzle assembly comprises a magnetic part interacting with the nozzlecoil, a valve needle part located below the magnetic part, a springacting between the magnetic part and the valve needle part, and a valveseat cooperating with the valve needle part.

In a further improved technical solution of the present invention, thenozzle assembly further comprises a first sleeve at least partiallyreceiving the magnetic part, and a second sleeve at least partiallyreceiving the valve needle part; the spring is mounted in the magneticpart and the valve needle part; the valve needle part is provided with atapered part, and a valve needle extending downward from the taperedpart; the first sleeve and the second sleeve are fixed together to forma space around the periphery of the valve needle part, and the valveneedle is provided with a through-hole in communication with the space.

In a further improved technical solution of the present invention, thenozzle assembly further comprises a rotational flow plate, manufacturedseparately from the valve seat and in close abutment with the valveseat, the rotational flow plate being provided with a number ofrotational flow grooves; the second sleeve is provided with acommunication groove establishing communication between the space andthe rotational flow grooves, and the valve seat is provided with aninjection hole cooperating with the valve needle.

In a further improved technical solution of the present invention, thewater-cooled base is provided with a mounting slot, a first coolingpassage, a second cooling passage spaced apart from the first coolingpassage, and an end cap sealed at the periphery of the mounting slot;between the end cap and the second sleeve, the nozzle assembly forms anannular cooling groove establishing communication between the firstcooling passage and the second cooling passage; the first coolingpassage is connected to an inlet connector to allow the injection of anengine coolant, and the second cooling passage is connected to an outletconnector to allow the engine coolant to flow out.

Also disclosed in the present invention is the following technicalsolution:

An exhaust gas post-processing system, comprising an injection system ofexhaust gas post-processing and an encapsulated system of exhaust gaspost-processing, wherein the injection system comprises the integratedapparatus described above, and the encapsulated system comprises asupport located downstream of the integrated apparatus.

In a further improved technical solution of the present invention, thesupport comprises selective catalytic reduction, and the encapsulatedsystem further comprises at least one mixer located between theintegrated apparatus and the support.

Also disclosed in the present invention is the following technicalsolution:

A control method for an integrated apparatus, the integrated apparatusbeing the integrated apparatus described above, the control methodcomprising:

driving the rotor to operate, thereby driving the pump to operate, anddrawing the fluid medium into the pump through the inlet passage;

after pressurization by the pump, delivering the fluid medium to thenozzle through the outlet passage;

when an injection condition is attained, energizing the nozzle coil, andat least partially opening the nozzle in order to inject the fluidmedium into intake gas or exhaust gas of the engine, wherein:

the electric machine coil and the nozzle coil are respectively subjectedto independent control.

Compared with the prior art, the integrated apparatus of the pump andthe nozzle according to the present invention integrates the pump andthe nozzle effectively, with a simple and compact structure, greatlyfacilitating installation by a customer. Furthermore, by controlling theelectric machine coil and the nozzle coil, interference between the pumpand nozzle is avoided, so the precision of control is improved. Based onthe integration of the urea pump and the urea nozzle in the integratedapparatus, due to the improvement in control precision, a suitable ratiocan be attained between the amount of urea injected into exhaust gas,and nitrogen oxides, reducing the risk of crystallization caused byexcessive injection of urea.

DESCRIPTION OF THE ACCOMPANYING DRAWINGS

FIG. 1 is a schematic diagram of the exhaust gas post-processing systemof the present invention when used for the processing of engine exhaustgas.

FIG. 2 is a schematic diagram of the integrated apparatus in FIG. 1.

FIG. 3 is a three-dimensional schematic view of the integrated apparatusof the present invention in an embodiment.

FIG. 4 is a three-dimensional schematic view of FIG. 3 from anotherangle.

FIG. 5 is a three-dimensional schematic view of FIG. 3 from anotherangle.

FIG. 6 is a main view of FIG. 3.

FIG. 7 is a right view of FIG. 3.

FIG. 8 is a bottom view of FIG. 5.

FIG. 9 is a top view of FIG. 5.

FIG. 10 is a partial three-dimensional exploded view of the integratedapparatus of the present invention, wherein the pump component and thenozzle component have been separated.

FIG. 11 is a partial three-dimensional exploded view of the integratedapparatus of the present invention, wherein the electric machine casingassembly has been isolated.

FIG. 12 is a three-dimensional schematic view of the electric machinecasing assembly in FIG. 11.

FIG. 13 is a three-dimensional schematic view of FIG. 12 from anotherangle.

FIG. 14 is a partial three-dimensional exploded view of FIG. 12.

FIG. 15 is a three-dimensional exploded view of FIG. 14 from anotherangle.

FIG. 16 is a further three-dimensional exploded view of FIG. 14, whereinthe electric machine coil has been isolated.

FIG. 17 is a further three-dimensional exploded view of FIG. 16, whereinthe electromagnetic shielding cover has been isolated.

FIG. 18 is a three-dimensional schematic view of the circuit board inFIG. 14 from another angle.

FIG. 19 is a further three-dimensional exploded view of FIG. 11.

FIG. 20 is a three-dimensional schematic view of the metal cover in FIG.19 from another angle.

FIG. 21 is a three-dimensional exploded view of FIG.

20.

FIG. 22 is a further three-dimensional exploded view of FIG. 19.

FIG. 23 is a further three-dimensional exploded view of FIG. 22.

FIG. 24 is a further three-dimensional exploded view of FIG. 23, whereinthe pump housing assembly, the nozzle assembly and the end cap, etc.have been isolated.

FIG. 25 is a three-dimensional view of the pump housing assembly in FIG.24.

FIG. 26 is a partial three-dimensional exploded view of FIG. 25.

FIG. 27 is a three-dimensional exploded view of the first housing andelements thereon in FIG. 26.

FIG. 28 is a three-dimensional exploded view of FIG. 27 from anotherangle.

FIG. 29 is a three-dimensional view of the first housing in FIG. 27.

FIG. 30 is a three-dimensional view of FIG. 29 from another angle.

FIG. 31 is a top view of FIG. 30.

FIG. 32 is a top view of FIG. 29.

FIG. 33 is a sectional schematic view along line C-C in FIG. 32.

FIG. 34 is a sectional schematic view along line D-D in FIG. 32.

FIG. 35 is a sectional schematic view along line E-E in FIG. 32.

FIG. 36 is a sectional schematic view along line F-F in FIG. 32.

FIG. 37 is a three-dimensional schematic view after removing the firsthousing in FIG. 26.

FIG. 38 is a partial three-dimensional exploded view of FIG. 37.

FIG. 39 is a top view of FIG. 37.

FIG. 40 is a further three-dimensional exploded view of FIG. 38.

FIG. 41 is a three-dimensional view of the second housing in FIG. 40.

FIG. 42 is a top view of FIG. 41.

FIG. 43 is a three-dimensional view of the third housing in FIG. 40.

FIG. 44 is a top view of FIG. 43.

FIG. 45 is a sectional schematic view along line G-G in FIG. 44.

FIG. 46 is a sectional schematic view along line H-H in FIG. 44.

FIG. 47 is a three-dimensional view of the nozzle assembly in FIG. 24.

FIG. 48 is a top view of FIG. 47.

FIG. 49 is a sectional schematic view along line I-I in FIG. 48.

FIG. 50 is a three-dimensional exploded view of FIG. 47.

FIG. 51 is a further three-dimensional exploded view of FIG. 50.

FIG. 52 is a three-dimensional view of the water-cooled base in FIG. 24.

FIG. 53 is a three-dimensional view of FIG. 52 from another angle.

FIG. 54 is a sectional schematic view along line A-A in FIG. 9.

FIG. 55 is a sectional schematic view along line B-B in FIG. 9.

FIG. 56 is a sectional schematic view along line J-J in FIG. 54.

FIG. 57 is a sectional schematic view along line K-K in FIG. 54.

FIG. 58 is a sectional schematic view along line L-L in FIG. 54.

FIG. 59 is a sectional schematic view along line M-M in FIG. 54.

FIG. 60 is a sectional schematic view along line N-N in FIG. 54.

FIG. 61 is a sectional schematic view along line O-O in FIG. 58.

FIG. 62 is a sectional schematic view along line P-P in FIG. 59.

FIG. 63 is a sectional schematic view along line Q-Q in FIG. 62.

FIG. 64 is a three-dimensional exploded view of the integrated apparatusof the present invention.

PARTICULAR EMBODIMENTS

Referring to FIG. 1, the present invention discloses an exhaust gaspost-processing system 100, which can be used to process exhaust gas ofan engine 10, reducing emissions of harmful substances so as to meet therequirements of emissions regulations. The exhaust gas post-processingsystem 100 comprises an injection system 200 of exhaust gaspost-processing and an encapsulated system 300 of exhaust gaspost-processing, wherein the injection system 200 comprises anintegrated apparatus 1 for pumping a urea solution from a urea tank 201(see arrow X) and injecting the urea solution into intake gas or exhaustgas of the engine 10 (e.g. into an exhaust pipe 106 or the encapsulatedsystem 300); the encapsulated system 300 comprises a mixer 301 locateddownstream of the integrated apparatus 1 and a support 302 locateddownstream of the mixer 301. Of course, in some embodiments, it is alsopossible for no mixer to be provided, or for two or more mixers to beprovided. The support 302 may for example be selective catalyticreduction (SCR), etc.

The engine 10 has an engine coolant circulation loop. Referring to FIG.1, in an embodiment shown in the figures of the present invention, theengine coolant circulation loop comprises a first circulation loop 101(see the thick arrow Y) and a second circulation loop 102 (see the thinarrow Z), wherein the first circulation loop 101 is used for cooling theintegrated apparatus 1, to reduce the risk of the latter being damagedby the heat of high-temperature engine exhaust gas; the secondcirculation loop 102 is used for heating the urea tank 201, to realize aheating and thawing function. It can be understood that in the firstcirculation loop 101, the integrated apparatus 1 is provided with aninlet connector 103 allowing an engine coolant to flow in, and an outletconnector 104 allowing the engine coolant to flow out; in the secondcirculation loop 102, it is provided with a control valve 105, to openor close the control valve 105 under appropriate conditions, realizingcontrol of the second circulation loop 102. A heating rod 202 connectedin the second circulation loop 102 is provided in the urea tank 201, toheat and thaw the urea solution using the temperature of the enginecoolant.

The integrated apparatus 1 of the present invention is described indetail below.

Referring to FIG. 2, in principle, the integrated apparatus 1 of thepresent invention integrates the functions of a urea pump 11 and a ureanozzle 12. The urea pump 11 comprises but is not limited to a gear pump,diaphragm pump, plunger pump or vane pump, etc. It should be understoodthat the term “integrated” used here means that the urea pump 11 and theurea nozzle 12 may be mounted as a single apparatus on a gas intake pipeor the exhaust pipe; or the urea pump 11 and the urea nozzle 12 areclose to each other and connected via a short connecting pipeline, andcan on the whole be regarded as one apparatus.

Furthermore, in order to subject the urea pump 11 and the urea nozzle 12to independent control, the exhaust gas post-processing system 100 ofthe present invention is also provided with a controller 13. It can beunderstood that the controller 13 may be integrated with the integratedapparatus 1 or arranged separately from the integrated apparatus 1.Referring to FIG. 2, in an embodiment shown in the figures of thepresent invention, the controller 13 is integrated in the integratedapparatus 1, to realize a high degree of integration of components, andmake installation at a customer end more convenient.

The integrated apparatus 1 is provided with a housing 14 foraccommodating the urea pump 11 and the urea nozzle 12. The embodimentshown in FIG. 2 merely shows the housing 14 roughly. For example, in anembodiment, the housing 14 is shared by the urea pump 11 and the ureanozzle 12; in another embodiment, the housing 14 is divided into a firsthousing cooperating with the urea pump 11 and a second housingcooperating with the urea nozzle 12, with the first housing and thesecond housing being fitted together, to form a whole. The housing 14 isprovided with an inlet passage 15 connected between the urea tank 201and the urea pump 11, and an outlet passage 16 connected between theurea pump and the urea nozzle 12. It must be explained that “inlet” inthe term “inlet passage 15” used here and “outlet” in “outlet passage16” take the urea pump 11 as a reference, i.e. the inlet is upstream ofthe urea pump 11, and the outlet is downstream of the urea pump 11. Theoutlet passage 16 is in communication with the urea nozzle 12, in orderto pump the urea solution toward the urea nozzle 12. It can beunderstood that the inlet passage 15 is located upstream of the ureapump 11, and is a low-pressure passage; the outlet passage 16 is locateddownstream of the urea pump 11, and is a high-pressure passage.

Furthermore, the integrated apparatus 1 is provided with a temperaturesensor 171 for detecting temperature. The temperature sensor 171 may beconfigured to be in communication with the inlet passage 15 and/or theoutlet passage 16; or the temperature sensor 171 may be configured to bemounted in any position in the integrated apparatus 1. A signal detectedby the temperature sensor 171 is transmitted to the controller 13; acontrol algorithm of the controller 13, designed on the basis of thisinputted signal and other signals, can improve the injection precisionof the urea nozzle 12. The integrated apparatus 1 is also provided witha pressure sensor 172 for detecting pressure; the pressure sensor 172 isin communication with the outlet passage 16, in order to detect pressurein the high-pressure passage of the outlet of the urea pump 11. Due tothe integrated design of the present invention, distances in theinterior passages are relatively short, therefore the position of thepressure sensor 172 may be regarded as being relatively close to theurea nozzle 12. An advantage of such a design is that the pressuremeasured by the pressure sensor 172 is relatively close to the pressurein the urea nozzle 12, so data precision is improved, thereby improvingthe injection precision of the urea nozzle 12. In an embodiment of thepresent invention, the temperature sensor 171 and the pressure sensor172 are two elements; in another embodiment of the present invention,the temperature sensor 171 and the pressure sensor 172 are one element,but simultaneously have the functions of detecting temperature andpressure.

Referring to FIG. 2, the integrated apparatus 1 is also provided with anoverflow element 173 connected between the outlet passage 16 and theinlet passage 15. The overflow element 173 comprises but is not limitedto an overflow valve, a safety valve or an electrical control valve,etc. The function of the overflow element 173 is to open the overflowelement 173 when the pressure in the high-pressure passage is higherthan a set value, and release urea solution located in the high-pressurepassage into the low-pressure passage or return it directly into theurea tank 201, to realize pressure regulation.

In order to drive the urea pump 11, the urea pump 11 is provided with anelectric machine coil 111 which communicates with the controller 13. Inorder to drive the urea nozzle 12, the urea nozzle 12 is provided with anozzle coil 121 which communicates with the controller 13.

The controller 13 communicates with the temperature sensor 171 and thepressure sensor 172, in order to transmit temperature signals andpressure signals to the controller 13. Of course, in order to be able toachieve precise control, the controller 13 may also receive othersignals, e.g. signals from a CAN bus which are associated with enginerunning parameters. Furthermore, the controller 13 may also obtain arotation speed of the urea pump 11; of course, the acquisition ofrotation speed signals may be realized by means of a correspondingrotation speed sensor 175 (hardware) or by means of a control algorithm(software). The rotation speed sensor 175 may be a Hall sensor, etc. Thecontroller 13 subjects the urea pump 11 and the urea nozzle 12respectively to independent control. An advantage of such control is theability to reduce the effect of actions of the urea pump 11 on the ureanozzle 12, in order to achieve relatively high control precision.

Furthermore, in certain operating conditions, since the exhaust gas ofthe engine has a high temperature, and the urea nozzle 12 is generallymounted on the exhaust pipe, it is necessary to cool the urea nozzle 12.For this purpose, the integrated apparatus 1 is also provided with acooling component, which cools the urea nozzle 12 by means of a coolingmedium. The cooling medium comprises but is not limited to air, and/orengine coolant, and/or lubricating oil, and/or urea, etc. Referring toFIG. 2, an embodiment shown in the figures of the present inventionemploys water cooling, i.e. uses engine coolant to cool the urea nozzle12. A cooling passage 141 for allowing engine coolant to circulate isprovided in the housing 14.

Referring to FIG. 2, the main principles of operation of the integratedapparatus 1 are as follows:

The controller 13 drives the urea pump 11 to operate; urea solutionlocated in the urea tank 201 is drawn into the urea pump 11 through theinlet passage 15, and after being pressurized, is delivered to the ureanozzle 12 through the outlet passage 16. Here, the controller 13acquires and/or calculates necessary signals, e.g. temperature,pressure, pump rotation speed, etc. When an injection condition isattained, the controller 13 issues a control signal to the urea nozzle12, e.g. energizes the nozzle coil 121, and realizes the injection ofurea by controlling the movement of a valve needle. The controller 13issues a control signal to the urea pump 11 to control the rotationspeed thereof, thereby stabilizing the pressure of the system. In anembodiment shown in the figures of the present invention, the controller13 subjects the urea pump 11 and the urea nozzle 12 respectively toindependent control.

Referring to FIGS. 3-37, from a structural point of view, in anembodiment shown in the figures of the present invention, the integratedapparatus 1 comprises a pump component 18 and a nozzle component 19.Referring to FIGS. 3-5, the nozzle component 19 is at least partiallyinserted into the pump component 18, and fixed thereto by welding.

Referring to FIGS. 3-13, in an embodiment shown in the figures of thepresent invention, the pump component 18 comprises an electric machinecasing assembly 181, a magnetic cover component 6 at least partiallylocated in the electric machine casing assembly 181, and a pump housingassembly 182 cooperating with the electric machine casing assembly 181.

Referring to FIGS. 6-9, the electric machine casing assembly 181comprises an electromagnetic shielding cover 183, the electric machinecoil 111 at least partially located in the electromagnetic shieldingcover 183, and the controller 13. In an embodiment shown in the figuresof the present invention, the electromagnetic shielding cover 183 ismade of a metal material in order to reduce interference from externalfactors affecting internal electronic components, etc. and at the sametime can also reduce the effect of internal electronic components onother external electronic devices. The electric machine casing assembly181 also comprises a cover shell 2 injection-molded at the periphery.The cover shell 2 comprises a cover shell cavity 21 for covering thecontroller 13 and at least a part of the pump component 18, athrough-hole 22 in communication with the cover shell cavity 21, and awaterproof gas-permeable cap 24 fixed in the through-hole 22. Theelectric machine coil 111 is electrically connected to the controller13. In an embodiment shown in the figures of the present invention, thecontroller comprises a circuit board 131 with a number of electroniccomponents arranged thereon. The electronic components will emit heatduring operation, causing air at the periphery thereof to expand;through the provision of the waterproof gas-permeable cap 24, thepresent invention effectively solves the problem of chips and/orelectronic components being damaged by pressure due to the expansion ofair, and at the same time can also achieve a waterproofing effect.Furthermore, the waterproof gas-permeable cap 24 can improve theenvironment of the controller 13, enabling it to satisfy operatingconditions.

In an embodiment shown in the figures of the present invention, thecircuit board 131 is annular, and is provided with a central hole 135located in a middle part. A connection insertion member 132 connected tothe circuit board is injection-molded on the cover shell 2. Furthermore,the electric machine casing assembly 181 also comprises a heatdissipating pad 130 covering a surface of the electronic components.With this configuration, the temperature of the electronic componentscan be made uniform by means of the heat dissipating pad 130, therebyavoiding damage to the electronic components due to local overheating.

The magnetic cover component 6 comprises a metal cover 62 at leastpartially inserted into the electric machine coil 111, a sheet part 61located below the metal cover 62, and a rotor 72 received in the metalcover 62, etc. The metal cover 62 protrudes upward from the sheet part61. The metal cover 62 passes through the central hole 135 of thecircuit board 131 in an upward direction, and is at least partiallyinserted into the electric machine coil 111. Referring to FIGS. 19-22,the sheet part 61 is screwed onto the pump housing assembly 182 by meansof a number of screws 133, in order to fix the magnetic cover component6. The pump component 18 also comprises an elastic body 71 received inthe metal cover 62 and located below the rotor 72; the elastic body 71can also be compressed in order to absorb an expansion volume caused bythe freezing of urea. Referring to FIG. 33, the electric machine coil111 is connected in a surrounding manner at the periphery of the metalcover 62.

The pump housing assembly 182 comprises a first housing 3, a secondhousing 4 and a third housing 5 which are stacked together in sequencefrom top to bottom. In an embodiment shown in the figures of the presentinvention, the first housing 3, the second housing 4 and the thirdhousing 5 are all made of a metal material.

In an embodiment shown in the figures of the present invention, the ureapump 11 is a gear pump, and comprises the electric machine coil 111, themetal cover 62, the rotor 72 located in the metal cover 62, a firstsealing ring 73 located below the metal cover 62, and a first gearcomponent 74 and a second gear component 75 which are meshed with eachother, etc. Since the gear pump can establish a relatively highoperating pressure, it is favorable for increasing the flow rate of theurea nozzle 12. Furthermore, the gear pump can also rotate in reverse,which is favorable for drawing out residual urea solution completely,reducing the risk of urea crystallizing.

Referring to FIGS. 14 to 28, in an embodiment shown in the figures ofthe present invention, the first housing 3, the second housing 4 and thethird housing 5 are machined members, and are fixed together by means ofbolts 66. The first housing 3 is provided with a laterally locatedengagement groove 34 and an O-shaped sealing ring 35 engaged in theengagement groove 34. In an embodiment shown in the figures of thepresent invention, the first housing 3 and the electric machine casingassembly 181 are fixed together by roll extrusion or welding, and pistonsealing is performed by means of the O-shaped sealing ring 35.

The first housing 3 comprises a first upper surface 31, a first lowersurface 32 and a first side 33, wherein the first upper surface 31 isprovided with a first annular groove 311 and a first island 312surrounded by the first annular groove 311. The first annular groove 311is used for receiving the first sealing ring 73. The sheet part 61presses down on the first sealing ring 73 to achieve sealing. The firstlower surface 32 is provided with a second annular groove 325 and asecond island 326 surrounded by the second annular groove 325. Thesecond annular groove 325 is used for receiving a second sealing ring731 (as shown in FIG. 16).

The first island 312 is provided with a first positioning hole 3121running through the first lower surface 32, a second positioning hole3122 running through the first lower surface 32, a first outlet hole3123 running through the first upper surface 31 and being incommunication with the outlet passage 16, and a first flow-guidinggroove 3124 running through the first upper surface 31 and being incommunication with the second positioning hole 3122. The urea pump 11 isprovided with a first shaft sleeve 76 received in the first positioninghole 3121, and a second shaft sleeve 77 received in the secondpositioning hole 3122. The first housing 3 also comprises a number offirst assembly holes 318 allowing the bolts 66 to pass through; thefirst assembly holes 318 run through the first upper surface 31 and thefirst lower surface 32. The first upper surface 31 is also provided witha sensor receiving hole 313, located at a side of the first island 312and used for receiving a sensor 174; the sensor 174 simultaneously hasthe functions of detecting temperature and pressure. The first housing 3is also provided with a second outlet hole 3125 establishingcommunication between the outlet passage 16 and the sensor receivinghole 313.

Furthermore, referring to FIG. 24, the first housing 3 is provided witha liquid entry passage 332, which runs through the first side 33 inorder to be connected to a urea connector 331. Referring to FIGS. 15 and16, the urea connector 331 comprises a filter mesh 3311 close to anouter side and a freeze-resistant element 3312 close to an inner side,wherein the filter mesh 3311 can filter impurities in the urea solution,and the freeze-resistant element 3312 can absorb an expansion volumewhen urea freezes, thereby reducing the risk of being damaged byfreezing. The first housing 3 is provided with a connecting hole 3127,which runs through the first lower surface 32 and is in communicationwith the liquid entry passage 332. The first outlet hole 3123 and theconnecting hole 3127 are both perpendicular to the liquid entry passage332. The first positioning hole 3121, the second positioning hole 3122and the connecting hole 3127 all run through the second island 326 in adownward direction. The first lower surface 32 is provided with a firstload release groove 321 establishing communication between the firstpositioning hole 3121 and the second positioning hole 3122, to ensurepressure balance. The first load release groove 321 is located on thesecond island 326. Furthermore, the first housing 3 is also providedwith a receiving cavity 322, which runs through the first lower surface32 in a downward direction and is used for receiving at least a part ofthe nozzle component 19. Referring to FIGS. 33 and 34, the receivingcavity 322 is in communication with the sensor receiving hole 313. Atthe same time, the receiving cavity 322 is also in communication withthe second outlet hole 3125.

Furthermore, referring to FIGS. 14 to 16, 22 and 24, the first housing 3is also provided with an overflow element receiving slot 319, which isin communication with the liquid entry passage 332 and the receivingcavity 322. The overflow element receiving slot 319 runs through thefirst side 33 in an outward direction, in order to receive the overflowelement 173. In an embodiment shown in the figures of the presentinvention, the overflow element 173 is a safety valve, and is intendedto ensure, by releasing pressure, that the pressure in the high-pressurepassage in the integrated apparatus 1 is within a range of safe values.In order to fix the overflow element 173, the first housing 3 isprovided with a plug 5122 for fixing the overflow element 173.

Referring to FIG. 1, the urea connector 331 is in communication with theurea tank 201 via a urea connecting pipe 333. In order to better realizethe function of heating and thawing, the exhaust gas post-processingsystem 100 may also be provided with a heating apparatus 334 for heatingthe urea connecting pipe 333. Referring to FIG. 24, in an embodimentshown in the figures of the present invention, the liquid entry passage332 extends horizontally into the interior of the first housing 3. Ofcourse, in other embodiments, the liquid entry passage 332 could also beat a certain angle.

Referring to FIGS. 25 to 27, the first gear component 74 comprises afirst gear shaft 741 and a first gear 742 fixed to the first gear shaft741; the second gear component 75 comprises a second gear shaft 751 anda second gear 752 fixed to the second gear shaft 751, with the firstgear 742 and the second gear 752 being meshed with each other. Referringto FIG. 34, in an embodiment shown in the figures of the presentinvention, the first gear 742 and the second gear 752 are meshedexternally. Furthermore, the first gear shaft 741 is a driving shaft,the second gear shaft 751 is a driven shaft, and the first gear shaft741 is higher than the second gear shaft 751. An upper end of the firstgear shaft 741 passes through the first shaft sleeve 76 and is fixed tothe rotor 72. An upper end of the second gear shaft 751 is positioned inthe second shaft sleeve 77. When the electric machine coil 111 isenergized, it interacts with a magnetic body 72; an electromagneticforce will drive the first gear shaft 741 to rotate, and thereby drivethe first gear 742 and the second gear 752 to rotate.

Referring to FIGS. 25 to 28, the second housing 4 is located below thefirst housing 3 and connected to the first housing 3. Furthermore, inorder to achieve better positioning, a number of positioning pins 328are also provided between the first housing 3 and the second housing 4.The second housing 4 comprises a second upper surface 41, a second lowersurface 42, and a gear slot 43 which runs through the second uppersurface 41 and the second lower surface 42 and is used for receiving thefirst gear 742 and the second gear 752. One side of the gear slot 43 isprovided with a liquid entry cavity 431 in communication with the inletpassage 15, and another side of the gear slot 43 is provided with aliquid exit cavity 432 in communication with the outlet passage 16.Specifically, the liquid entry cavity 431 is in communication with theconnecting hole 3127, and an upper end of the liquid exit cavity 432 isin communication with the first outlet hole 3123. Furthermore, in orderto improve the freeze-resistance of the product, the second housing 4 isalso provided with a first freeze-resistant rod 441 located in theliquid entry cavity 431 and a second freeze-resistant rod 442 located inthe liquid exit cavity 432; the first freeze-resistant rod 441 and thesecond freeze-resistant rod 442 can both be compressed when ureafreezes.

Furthermore, the second housing 4 is also provided with an accommodatinghole 411 allowing at least a part of the nozzle component 19 to passthrough. The nozzle component 19 partially protrudes from the secondupper surface 41 in an upward direction and is received in the receivingcavity 322. With this configuration, high-pressure urea solution can bedelivered to the urea nozzle 12. The second housing 4 also comprises anumber of second assembly holes 418 aligned with the first assemblyholes 318.

Referring to FIG. 28, the third housing 5 is located below the secondhousing 4 and connected to the second housing 4. The third housing 5comprises a body part 51, a protruding part 52 extending downward fromthe body part 51, and a flange 53 extending outward from the body part51, wherein the flange 53 is provided with a number of third assemblyholes 531 aligned with the second assembly holes 418, for allowing thebolts 66 to pass through. The body part 51 is provided with a thirdupper surface 511; the third upper surface 511 is provided with a thirdannular groove 512 and a third island 513 surrounded by the thirdannular groove 512. The third annular groove 512 is used for receiving athird sealing ring 732.

During operation, urea solution enters the liquid entry passage 332 fromthe urea connecting pipe 333, and enters the liquid entry cavity 431 viathe connecting hole 3127; after being pressurized by the gear pump, aportion of high-pressure urea solution passes through the first outlethole 3123 in an upward direction and enters the metal cover 62, andanother portion of high-pressure urea solution enters a secondflow-guiding groove 5114 and a third flow-guiding groove 5115 in adownward direction; a portion of urea solution located in the metalcover 62 enters the second shaft sleeve 77 from the first flow-guidinggroove 3124, and then enters the first shaft sleeve 76 via the firstload release groove 321, in order to improve the smoothness of rotationof the gear pump, and reduce wear; another portion of urea solutionlocated in the metal cover 62 enters the receiving cavity 322 from thesecond outlet hole 3125 in order to flow toward the nozzle component 19,and at the same time a portion of urea solution flows toward theoverflow element 173. When the pressure is less than a set value of theoverflow element 173, the overflow element 173 is closed; when thepressure is greater than a set value of the overflow element 173, theoverflow element 173 opens, and a portion of urea solution enters theliquid entry passage 332, to achieve pressure release.

It can be understood that in an embodiment shown in the figures of thepresent invention, the inlet passage 15 comprises the liquid entrypassage 332, the connecting hole 3127 and the liquid entry cavity 431.Due to being located upstream of the urea pump 11, the inlet passage 15is called the low-pressure passage. The outlet passage 16 comprises theliquid exit cavity 432, the first outlet hole 3123, the second outlethole 3125 and the receiving cavity 322, etc. Due to being locateddownstream of the urea pump 11, the outlet passage 16 is called thehigh-pressure passage.

Referring to FIGS. 13 and 29 to 32, the nozzle component 19 comprises anozzle assembly 120 and a water-cooled base 190 connected in asurrounding manner at the outside of the nozzle assembly 120. In anembodiment shown in the figures of the present invention, the nozzleassembly 120 and the water-cooled base 190 together form the urea nozzle12.

In an embodiment shown in the figures of the present invention, thenozzle assembly 120 comprises a nozzle coil 121, a magnetic part 81interacting with the nozzle coil 121, a valve needle part 82 locatedbelow the magnetic part 81, a spring 83 which acts between the magneticpart 81 and the valve needle part 82, and a valve seat 84 whichcooperates with the valve needle part 82 (see FIG. 30), etc. The nozzlecoil 121 is located at the periphery of the magnetic part 81; the nozzleassembly 120 also comprises a first sleeve 811 which at last partiallyreceives the magnetic part 81, and a second sleeve 812 which at leastpartially receives the valve needle part 82. Furthermore, the nozzleassembly 120 also comprises a sleeve part 122 connected in a surroundingmanner at the periphery of the nozzle coil 121. The spring 83 is mountedin the magnetic part 81 and the valve needle part 82. The valve needlepart 82 is provided with a tapered part 821, and a valve needle 822extending downward from the tapered part 821.

The first sleeve 811 and the second sleeve 812 are fixed together toform a space 813 around the periphery of the valve needle part 82; thevalve needle 822 is provided with a through-hole 814 in communicationwith the space 813. The nozzle assembly 120 also comprises a rotationalflow plate 85, which is manufactured separately from the valve seat 84and is in close abutment with the valve seat 84; the rotational flowplate 85 is provided with a number of rotational flow grooves 851. Thesecond sleeve 812 is provided with a communication groove 815establishing communication between the space 813 and the rotational flowgrooves 851. The valve seat is provided with an injection hole 841cooperating with the valve needle 822.

Referring to FIG. 30, a fourth sealing ring 816 is connected in asurrounding manner to an upper end of the magnetic part 81, in order toachieve sealing with an inner wall of the receiving cavity 322.Furthermore, the nozzle assembly 120 also comprises a terminalencapsulation part 86 connected to the nozzle coil 121; a fifth sealingring 817 is connected in a surrounding manner to the terminalencapsulation part 86.

The water-cooling base 190 comprises a main body part 91, a mountingslot 92 running through the main body part 91 in a downward direction,and a mounting flange 93 extending outward from the main body part 91.The mounting flange 93 is provided with a number of mounting holes 931for mounting the integrated apparatus 1 onto the exhaust pipe 106 or theencapsulated system 300.

The cooling passage 141 located in the water-cooled base 190 comprises afirst cooling passage 913, and a second cooling passage 914 spaced apartfrom the first cooling passage 913. The first cooling passage 913 is incommunication with the inlet connector 103; the second cooling passage914 is in communication with the outlet connector 104. The water-cooledbase 190 is provided with an end cap 96 sealed at the periphery of themounting slot 92 (see FIG. 33). In an embodiment shown in the figures ofthe present invention, the end cap 96 is welded in the mounting slot 92.With this configuration, the water-cooled base 190 forms an annularcooling groove 916 establishing communication between the first coolingpassage 914 and the second cooling passage 915, between the end cap 96and the second sleeve 812.

In an embodiment shown in the figures of the present invention, themounting flange 93 and the main body part are integrally formed bymachining. Of course, in other embodiments, the mounting flange 93 couldalso be manufactured separately from the main body part 91, and thenwelded thereto.

It can be understood that in other embodiments of the present invention,for example the integrated apparatus is used for the injection of fuelinto engine exhaust gas, in order to achieve the regeneration of adownstream diesel particulate filter (DPF). In such an application, theurea pump 11 may be replaced by a fuel pump, the urea nozzle 12 may bereplaced by a fuel nozzle, and the urea solution may be replaced byfuel. Such a change is understandable to a person skilled in the art,and is not further described superfluously here.

To facilitate understanding of the present invention, the urea pump andthe fuel pump are collectively called pumps, the urea nozzle and thefuel nozzle are collectively called nozzles, and the urea solution andthe fuel are collectively called fluid media.

Compared with the prior art, the integrated apparatus 1 of the presentinvention has an integrated design, which can omit or shorten the ureapipe used for connecting the pump to the nozzle in the prior art, canalso omit insertion connection members between various sensors and wirebundles in the pump supply unit in the prior art, and need not have anyheating/thawing apparatus, so reliability is high. The integratedapparatus 1 of the present invention is structurally compact, small involume, and easy to mount in various models of vehicle. Furthermore,internal fluid medium passages in the integrated apparatus 1 of thepresent invention are short, with a small pressure drop; dead volumebetween the pump and the nozzle is small, and efficiency is high. Thesensor 174 is close to the nozzle, and injection pressure precision ishigh. Furthermore, by subjecting the pump and the nozzle respectively toindependent control, a situation where an action of the nozzle is drivenby an action of the pump is avoided, and the precision of control isthereby improved. Due to the fact that the injection precision of thenozzle is improved, a suitable ratio can be attained between the amountof urea injected into exhaust gas, and nitrogen oxides, reducing therisk of crystallization caused by excessive injection of urea. Theintegrated apparatus 1 of the present invention may employ watercooling, such that the temperature of urea remaining in the integratedapparatus 1 is unable to reach the crystallization point, socrystallization will not readily occur.

The embodiments above are merely intended to explain the presentinvention, without limiting the technical solution described by thepresent invention. An understanding of this Description should takethose skilled in the art as a foundation. Although the present inventionhas been explained in detail herein with reference to the embodimentsabove, those of ordinary skill in the art should understand that thoseskilled in the art could still make amendments to or equivalentsubstitutions in the present invention, and all technical solutions andimprovements thereof which do not diverge from the spirit and scope ofthe present invention should be included in the scope of the claims ofthe present invention.

1. An integrated apparatus of a pump and a nozzle, wherein the pump isused for pumping a fluid medium toward the nozzle, and the nozzle isused for injecting the fluid medium into intake gas or exhaust gas of anengine, characterized in that the integrated apparatus comprises a pumpcomponent and a nozzle component; the pump component comprises anelectric machine casing assembly, a magnetic cover component at leastpartially located in the electric machine casing assembly, and a pumphousing assembly cooperating with the electric machine casing assembly;the electric machine casing assembly comprises an electromagneticshielding cover, and an electric machine coil at least partially locatedin the electromagnetic shielding cover; the magnetic cover componentcomprises a metal cover at least partially inserted into the electricmachine coil, and a rotor received in the metal cover; the electricmachine casing assembly and the pump housing assembly are fixed togetherby roll extrusion or welding; the pump housing assembly comprises aninlet passage located upstream of the pump and in communication with thepump, and an outlet passage located downstream of the pump and incommunication with the pump, wherein the outlet passage is incommunication with the nozzle component; the pump housing assemblyfurther comprises a first gear component and a second gear componentmeshed with each other, wherein the first gear component comprises afirst gear shaft and a first gear, the second gear component comprises asecond gear shaft and a second gear, the first gear and the second gearbeing meshed with each other, and the rotor being fixed to the firstgear shaft; the nozzle component comprises a nozzle assembly, and awater-cooled base connected in a surrounding manner at the outside ofthe nozzle assembly, wherein the nozzle assembly comprises a nozzle coilfor driving the nozzle.
 2. The integrated apparatus as claimed in claim1, wherein the pump is a urea pump, the nozzle is a urea nozzle, and thefluid medium is a urea solution.
 3. The integrated apparatus as claimedin claim 1, wherein the pump is a fuel pump, the nozzle is a fuelnozzle, and the fluid medium is a fuel.
 4. The integrated apparatus asclaimed in claim 2, wherein the controller subjects the urea pump andthe urea nozzle respectively to independent control; the electricmachine casing assembly comprises a controller, the controllercomprising a circuit board, with the electric machine coil and thenozzle coil both being connected to the circuit board.
 5. The integratedapparatus as claimed in claim 2, wherein the integrated apparatuscomprises a sensor, in communication with the outlet passage in order todetect temperature and pressure, and an overflow element connectedbetween the outlet passage and the inlet passage.
 6. The integratedapparatus as claimed in claim 2, wherein the first gear shaft is adriving shaft, the second gear shaft is a driven shaft, and the firstgear shaft is higher than the second gear shaft.
 7. The integratedapparatus as claimed in claim 2, wherein a freeze-resistant body locatedabove the rotor is further provided in the metal cover, thefreeze-resistant body being compressible in order to absorb an expansionvolume caused by the freezing of urea.
 8. The integrated apparatus asclaimed in claim 7, wherein the pump component further comprises anelastic body received in the metal cover and located below the rotor,the elastic body being compressible in order to absorb an expansionvolume caused by the freezing of urea.
 9. The integrated apparatus asclaimed in claim 2, wherein the pump housing assembly is provided with agear slot receiving the first gear and the second gear, the first gearand the second gear are meshed externally, one side of the gear slot isprovided with a liquid entry cavity in communication with the inletpassage, and another side of the gear slot is provided with a liquidexit cavity in communication with the outlet passage.
 10. The integratedapparatus as claimed in claim 9, wherein the pump housing assembly isfurther provided with a first freeze-resistant rod located in the liquidentry cavity and a second freeze-resistant rod located in the liquidexit cavity; the first freeze-resistant rod and the secondfreeze-resistant rod are both compressible when urea freezes.
 11. Theintegrated apparatus as claimed in claim 1, wherein the nozzle assemblycomprises a magnetic part interacting with the nozzle coil, a firstsleeve at least partially receiving the magnetic part, a valve needlepart located below the magnetic part, a second sleeve at least partiallyreceiving the valve needle part, a spring acting between the magneticpart and the valve needle part, a valve seat cooperating with the valveneedle part, and a rotational flow plate which is manufacturedseparately from the valve seat and is in close abutment with the valveseat; the rotational flow plate is provided with a number of rotationalflow grooves.
 12. The integrated apparatus as claimed in claim 11,wherein the nozzle coil is located at the periphery of the magneticpart, the valve needle part is provided with a valve needle, the firstsleeve and the second sleeve are fixed together to form a space aroundthe periphery of the valve needle part, the valve needle is providedwith a through-hole in communication with the space, the second sleeveis provided with a communication groove establishing communicationbetween the space and the rotational flow grooves, and the valve seat isprovided with an injection hole cooperating with the valve needle. 13.The integrated apparatus as claimed in claim 1, wherein the electricmachine casing assembly is provided with an injection-molded connectioninsertion member electrically connected to the circuit board, a numberof electronic components are mounted on the circuit board, and theelectric machine casing assembly further comprises a heat dissipatingpad covering a surface of the electronic components.
 14. The integratedapparatus as claimed in claim 9, wherein the magnetic cover componentcomprises a sheet part located below the metal cover, the sheet partbeing fixed to the pump housing assembly by means of a number of screws.15. The integrated apparatus as claimed in claim 14, wherein the pumphousing assembly comprises a first housing, the first housing comprisinga first upper surface, a first lower surface and a first side, whereinthe first upper surface is provided with a first annular groove, a firstisland surrounded by the first annular groove, and a first sealing ringreceived in the first annular groove, with the sheet part pressing downon the first sealing ring; the first island is provided with a firstpositioning hole running through the first lower surface, and a secondpositioning hole running through the first lower surface; the urea pumpcomprises a first shaft sleeve received in the first positioning hole,and a second shaft sleeve received in the second positioning hole,wherein the first gear shaft is inserted into the first shaft sleeve,and the second gear shaft is inserted into the second shaft sleeve. 16.The integrated apparatus as claimed in claim 15, wherein the first lowersurface is provided with a first load release groove establishingcommunication between the first positioning hole and the secondpositioning hole.
 17. The integrated apparatus as claimed in claim 15,wherein the first island further comprises a first flow-guiding grooverunning through the first upper surface and in communication with thesecond positioning hole, and a first outlet hole running through thefirst upper surface and in communication with the liquid exit cavity;the first upper surface is further provided with a sensor receivinghole, located at a side of the first island and used for receiving asensor, and the integrated apparatus comprises the sensor for detectingtemperature and pressure; the first housing is further provided with asecond outlet hole in communication with the sensor receiving hole. 18.The integrated apparatus as claimed in claim 17, wherein the firsthousing is provided with an overflow element receiving slot, and theintegrated apparatus is provided with an overflow element mounted in theoverflow element receiving slot; when a pressure of the outlet passageis higher than a set value, the overflow element opens in order toreturn a portion of the urea solution into the inlet passage.
 19. Theintegrated apparatus as claimed in claim 15, wherein the pump housingassembly comprises a second housing, located below the first housing andconnected to the first housing; the second housing comprises a secondupper surface and a second lower surface, with the gear slot runningthrough the second upper surface and the second lower surface.
 20. Theintegrated apparatus as claimed in claim 19, wherein the pump housingassembly comprises a third housing, located below the second housing andconnected to the second housing; the third housing comprises a bodypart, and a protruding part extending downward from the body part,wherein the body part is provided with a third upper surface, with thethird upper surface being provided with a third annular groove and athird island surrounded by the third annular groove; the third island isprovided with a third positioning hole and a fourth positioning holerunning through the third upper surface, the third positioning hole andthe fourth positioning hole extending into the protruding part; the ureapump comprises a third shaft sleeve received in the third positioninghole, and a fourth shaft sleeve received in the fourth positioning hole,wherein the first gear shaft is inserted into the third shaft sleeve,and the second gear shaft is inserted into the fourth shaft sleeve. 21.The integrated apparatus as claimed in claim 20, wherein the thirdisland is provided with a second flow-guiding groove and a thirdflow-guiding groove running through the third upper surface, wherein thesecond flow-guiding groove is in communication with the thirdpositioning hole, and the third flow-guiding groove is in communicationwith the fourth positioning hole.
 22. The integrated apparatus asclaimed in claim 20, wherein the nozzle assembly comprises a magneticpart interacting with the nozzle coil, a valve needle part located belowthe magnetic part, a spring acting between the magnetic part and thevalve needle part, and a valve seat cooperating with the valve needlepart.
 23. The integrated apparatus as claimed in claim 22, wherein thenozzle assembly further comprises a first sleeve at least partiallyreceiving the magnetic part, and a second sleeve at least partiallyreceiving the valve needle part; the spring is mounted in the magneticpart and the valve needle part; the valve needle part is provided with atapered part, and a valve needle extending downward from the taperedpart; the first sleeve and the second sleeve are fixed together to forma space around the periphery of the valve needle part, and the valveneedle is provided with a through-hole in communication with the space.24. The integrated apparatus as claimed in claim 23, wherein the nozzleassembly further comprises a rotational flow plate, manufacturedseparately from the valve seat and in close abutment with the valveseat, the rotational flow plate being provided with a number ofrotational flow grooves; the second sleeve is provided with acommunication groove establishing communication between the space andthe rotational flow grooves, and the valve seat is provided with aninjection hole cooperating with the valve needle.
 25. The integratedapparatus as claimed in claim 24, wherein the water-cooled base isprovided with a mounting slot, a first cooling passage, a second coolingpassage spaced apart from the first cooling passage, and an end capsealed at the periphery of the mounting slot; between the end cap andthe second sleeve, the nozzle assembly forms an annular cooling grooveestablishing communication between the first cooling passage and thesecond cooling passage; the first cooling passage is connected to aninlet connector to allow the injection of an engine coolant, and thesecond cooling passage is connected to an outlet connector to allow theengine coolant to flow out.
 26. An exhaust gas post-processing system,comprising an injection system of exhaust gas post-processing and anencapsulated system of exhaust gas post-processing, wherein theinjection system comprises the integrated apparatus as claimed in claim1, and the encapsulated system comprises a support located downstream ofthe integrated apparatus.
 27. The exhaust gas post-processing system asclaimed in claim 26, wherein the support comprises selective catalyticreduction, and the encapsulated system further comprises at least onemixer located between the integrated apparatus and the support.
 28. Acontrol method for an integrated apparatus, wherein the integratedapparatus is the integrated apparatus as claimed in claim 1, the controlmethod comprising: driving the rotor to operate, thereby driving thepump to rotate, and drawing the fluid medium into the pump through theinlet passage; after pressurization by the pump, delivering the fluidmedium to the nozzle through the outlet passage; when an injectioncondition is attained, energizing the nozzle coil, and at leastpartially opening the nozzle in order to inject the fluid medium intointake gas or exhaust gas of the engine, wherein: the electric machinecoil and the nozzle coil are respectively subjected to independentcontrol.